1. Field of the Invention
The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display (LCD) device and a fabricating method thereof.
2. Discussion of the Related Art
Until recently, display devices have typically used cathode-ray tubes (CRTs). Presently, many efforts are being made to study and develop various types of flat panel displays, such as liquid crystal display (LCD) devices, plasma display panels (PDPs), field emission displays (FED), and electro-luminescence displays (ELDs), as a substitute for CRTs. Of these types of flat panel displays, the LCD devices have many advantages, such as high resolution, light weight, thin profile, compact size, and low voltage power supply requirements.
In general, an LCD device includes two substrates that are spaced apart and face each other with a liquid crystal material interposed between the two substrates. The two substrates include electrodes that face each other such that a voltage applied between the electrodes induces an electric field across the liquid crystal material. Alignment of the liquid crystal molecules in the liquid crystal material changes in accordance with the intensity of the induced electric field into the direction of the induced electric field, thereby changing the light transmissivity of the LCD device. Thus, the LCD device displays images by varying the intensity of the induced electric field.
FIG. 1 is a perspective view of an LCD device according to the related art. As shown in FIG. 1, the LCD device 11 includes a first substrate 22, a second substrate 5 and a liquid crystal material 14. The second substrate 5 is referred to as a color filter substrate that includes a color filter pattern 8, a black matrix 6 between the color filter patterns 8, and a common electrode 18 on both the color filter pattern 8 and the black matrix 6. The first substrate 22 is referred to as an array substrate that includes a data line 15 and a gate line 13 that cross each other to define a pixel region P. A pixel electrode 17 and a thin film transistor T, as a switching element, are positioned in each pixel region P. Thin film transistors T, which are disposed adjacent to where the data lines 15 and the gate lines 13 cross, are disposed in a matrix form on the first substrate 22. The gate line 13 and a storage electrode 30 overlap the gate line 13 to define a storage capacitor C.
The first and second substrates 22 and 5 have patterns that block light. The first and second substrates 22 are aligned to each other and then attached. There is a possibility of light leakage in the LCD device due to a misalignment between the first and second substrates 22 and 5.
FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1. As shown in FIG. 2, a thin film transistor T in a switching region S includes a gate electrode 32, a semiconductor pattern 34, a source electrode 36 and a drain electrode 38 disposed on the first substrate 22. A passivation layer 40 is disposed on the thin film transistor T. A pixel electrode 17 is disposed on the passivation layer 40 in each pixel region P. A storage capacitor C includes a gate line 13 and a storage electrode 30 overlapping the gate line 13. A black matrix 6 corresponding to a gate line 13, a data line 15 and a thin film transistor T is disposed on the second substrate 5. Red, green and blue color filter patterns 7a, 7b and 7c corresponding to respective pixel regions P are also disposed on the second substrate 5. A liquid crystal material 14 is interposed between the first and second substrates 22 and 5.
To prevent cross-talk, the data line 15 and the gate line 13 are spaced apart from the pixel electrode 17 by a first distance Al and a second distance A2, respectively. Since light leakage can occur through the areas defined by the first and second distances A1 and A2, the black matrix 6 covers the areas defined by first and second distances A and B. Further, the black matrix 6 blocks incident light from affecting the semiconductor pattern 34. Due to the possibility of misalignment during attachment of the first and second substrates 22 and 5, the black matrix 6 has a margin of error to compensate for misalignment. Thus, an aperture ratio of the LCD is reduced by margin of error for the black matrix 6. When misalignment during attachment of the first and second substrates 22 and 5 is greater than the margin of error, some of the areas defined by the first and second distances A1 and A2 are not covered by the black matrix 6 so that light leakage occurs.